This invention relates to a system for removing solids from a well bore and reclaiming the well bore fluid. More particularly, but not by way of limitation, this invention relates to a system and method for removing solids from an oil and gas well bore utilizing a work string, and thereafter, reclaiming the well bore fluid.
In the oil and gas industry, a well is drilled and completed to a hydrocarbon bearing zone from which hydrocarbons are produced. During the life of the well, sand is many times produced from the reservoirs. The sand can build up within the well bore as is well understood by those of ordinary skill in the art.
Operators have found it necessary to remove the sand, debris and other solids that accumulates within the well bore. The sand can cause numerous operational problems, some of which may result in hazardous and/or dangerous conditions. Hence, the sand, debris and other solids require removal.
In the past, operators have run a work string within the well bore in order to wash out the sand and debris. Work strings include coiled tubing, snubbing pipe, drill strings, and other tubulars. One of the problems faced by such an operation includes contamination of the well bore fluid with the sand, debris and other solids. After completion of the wash operation, the well bore fluid has to be separated.
Well bore fluids have become quite sophisticated over the years. As those of ordinary skill in the art will recognize, compatible well bore fluids must be placed into the wells in order to enhance production, decrease corrosion and increase reservoir life. The well bore fluids can become quite costly, and therefore, conservation of the fluids is advantageous. Examples of well bore fluids include, but certainly not limited to, brine, zinc chloride, barite, etc.
The prior art systems of separating, cleaning, and/or reclaiming the well bore fluids have proved to be costly and inefficient. For instance, sock filters have been utilized to filter out the solids. However, the filters become clogged quickly. Further, it is a time consuming practice to exchange dirty filters with clean filters.
Additionally, most of the solid removal operations occur on platforms, semi-ssubmersibles, jack-ups, etc that contain drilling rigs. Therefore, the systems use a cumbersome assembly of shale shakers, settling tanks and charger pumps that are generally associated with drilling systems. These prior art systems take up space, cost significant sums of money and are inefficient.
Presently, the well bore fluid with entrained solids is directed through a shale shaker. Underneath the shale shacker is a settling tank. The well bore fluid is then directed to a centrifuge via a charger pump. Thereafter, the well bore fluid is directed to a main tank. The well bore fluid is then pumped backed into the well bore from this main tank. This is a cumbersome and expense system.
Therefore, there is a need for a system for removing solids from a well bore that takes up a minimum of space and is economical. Further, there is a need for a method of utilizing a work string to clean out sand and debris, and thereafter, reclaim the well bore fluid for further use. There is also a need for a method for reclaiming well bore fluids such as brine when the brine is used to clean out a well bore with a coiled tubing string. These and many other needs will be met by the invention herein disclosed.